#比较大小
a = 10
b = 20
c = 30
if a > b:
    if a > c:
        print("a is bigger than c")
    else:
        print("c is bigger than a")
    if b > c:
        print()
    else:
        print()

if a > b and b > c:
    print()
elif b > a and c > b:
    print()
